Q DIAGRAMS


These diagrams are for GPO intercom telephones, the HES and HTS ranges.

HES 1 and 2 - Q100 to Q306
HES No. 3 - Q400 to Q447
HES No. 4 - Q500 to Q583
HTS No. 1 - Q351 to Q353
HTS No. 2 - Q361 to Q362
 

No. Title of diagram
Q100 Numerical index of diagrams (only goes up to Q301)
Q101 Subject Index of Diagrams
Q102 Plug & Jack wiring for Telephone Intercom No. 1
Q103 Plug & Jack wiring for Unit, Transfer Intercom No. 1 or 1A
Q104 Plug & Jack wiring for Unit, Transfer Intercom No. 1
Q110 Illustration of Labels No. 222 A-H for use with Telephone Intercom No. 1/1 & 1/2
Q111 Typical Schematic layout for system unit
Q112 Typical Schematic for system with 1 exchange line, 5 internal extensions
Q113 Typical wiring of junction box used for feeding local stations
Q114 Typical wiring of junction box
Q115 Cable Terminations
Q131 Telephone Intercom No. 1/1
Q132 Unit Transfer, Intercom No. 1 (Mk 2)
Q133 Unit Transfer, Intercom No. 1A (Mark 2)
Q134 Telephone Intercom No. 1/1B (Mark 2) for use with Repeater Telephonic No. 17C
Q135 Telephone Intercom No. 1/1A and 1/2A with Handset No. 4
Q141 Telephone Intercom No. 1/1
Q142 Unit Transfer Intercom No. 1 Unit to plug wiring
Q143 Unit Transfer Intercom No. 1A (Mk 1 & 2)
Q144 Telephone Intercom No. 1/1B (Mark 2) Telephone to plug wiring
Q151 Alternative arrangement of junction boxes
Q152 Plug point connections on instruments and units
Q153 Unit Transfer Intercom No. 1
Q154 Unit Transfer Intercom No. 1A
Q155 Unit Transfer Intercom No. 2
Q156 Unit Transfer Intercom No. 3
Q157 Connections of Dial, Automatic No. 10 when fitted to Telephone Intercom No. 1 or 2
Q158 Using Telephone Intercom No. 1/1B and Repeater Telephonic 17C
Q160 Facilities between PBX extension - Explanatory for one station
Q161 Facilities between PBX Extensions, plan extension instrument
Q170 Unit Transfer Intercom No. 1A (Mks 1&2) & No. 3 - Relay Adjustments
Q199 Non-multiple termination for loud sounding bell, hooter or lamp signal
Q202 Plug & Jack wiring for Unit Transfer Intercom No. 2
Q203 Plug & Jack wiring for Unit Transfer Intercom No. 2
Q204 Plug & Jack wiring for Unit Transfer Intercom No. 3
Q205 Plug & Jack wiring for Unit Transfer Intercom No. 2
Q206 Facilities between PBX Extensions - 2+10 System - Plug & jack wiring for telephone intercom No. 1 etc
Q208 Facilities between PBX Extensions - 2+10 System - explanatory of connexions
Q209 Facilities between PBX Extensions - 2+10 system - plan extension instrument
Q210 Facilities between PBX Extensions - 2+20 System - typical schematic layout
Q211 Typical layout for system with 1 or 2 Exch lines etc
Q212 Typical schematic layout for system with 1 or 2 Exch lines, 10 internal extns etc
Q213 Typical wiring of junction box
Q214 Typical wiring of junction box for feeding terminal stations etc
Q215 Typical wiring of main junction box
Q216_1
Q216_2
Typical wiring of auxiliary junction box used at 1st choice main station
Typical wiring of auxiliary junction box used at 1st choice main station
Q218 Facilities between PBX Extensions 2+10 system, typical wiring
Q219 Facilities between PBX Extensions 2+10 System Typical wiring
Q220 Facilities between PBX Extensions 2+10 System Typical wiring of intermediate junction boxes
Q221 Facilities between PBX Extensions 2+10 System. Typical wiring of terminal junction box
Q231 Telephone Intercom No's 1/2, 1/2A & 1/2AL
Q232 Unit Transfer Intercom No. 2 (Mk 2)
Q233 Unit Transfer Intercom No. 3 - relay adjustments
Q235 Telephone Intercom No. 1/2B (Mk 2)
Q241 Telephone Intercom No's 1/2 & 1/2A Mks 1 & 1A & 2 & 2A & 1/2AL Mks 2, 2A & 3A
Q242 Unit Transfer Intercom No. 2 (Mk 1 & 2)
Q243_1
Q243_2
Unit Transfer Intercom No. 3 Unit to plug wiring
Unit Transfer Intercom No. 3 Unit to plug wiring
Q244 Telephone Intercom No. 1/2B Mk 2
Q301 Magneto exchange termination
Q302 Explanatory Elements - calling & speaking to multiple station
Q303 Explanatory Elements - engaged exchange line
Q304 Explanatory Elements - Multiple station calling & speaking to exchange
Q305 Explanatory Elements - Barred & Restricted exchange access
Q306 Explanatory elements - non-multiple station
Q351 House Telephone System No. 1 - Telephone House No. 104 & 105 Internal wiring
Q352 House Telephone System No. 1 - 15 Line Instruments
Q353 House Telephone System No. 1 - Explanatory Elements
Q361 House Telephone System No. 2 - Telephone types (500 range)
Q362 House Telephone System No. 2 - Cabling for Telephones, House No's 500 and 501
Q400 HES No. 3 Numerical Index of Diagrams
Q401 HES No. 3 Alphabetical Index of Diagrams
Q402 HES No. 3 Layout of typical system
Q403 HES No. 3 Typical Multiple Connexions Schematic
Q404 HES No. 3 Typical Multiple Connexions Wiring
Q405 HES No. 3 Relay Unit Q405 Common Equipment
Q406 HES No. 3 Alternative layout with spur multiple stations (typical)
Q407 HES No. 3 Exchange Prohibition
Q408 HES No. 3 Exchange Service Barred Relay Unit Q408
Q409 HES No. 3 Exchange Line Monitoring Relay Unit Q409
Q410 HES No. 3 Relay Unit Q410 Common Equipment with provision for a non-multiple extension
Q411 HES No. 3 Provision of individual exchange or PABX line at a multiple station
Q412 HES No. 3 Provision of subscriber’s private meter (Meter No. 19)
Q413 HES No. 3 Provision of operator recall
Q415 HES No. 3 Relay Unit Q415 for terminating Private & Switchboard Circuits
Q417 HES No. 3 Alternative ringing arrangements
Q419 HES No. 3 Extension bells and buzzers
Q420 HES No. 3 Non-multiple extension using Telephone No. 710
Q422 HES No. 3 Telephone Intercom No. 3/1L
Q423 HES No. 3 Switch Composite No. 1A for use with Telephone Intercom No. 3/1
Q424 HES No. 3 Telephone Intercom No. 3/1 Installation
Q425 HES No. 3 Extension Plans 107, 107A, 105, 105A at non-multiple extensions
Q426 HES No. 3 Non-multiple extension Plan 1 (internal only) using Telephone No. 710
Q427 HES No. 3 Non-multiple extension Plan 1A (internal only) using Telephone No. 710
Q428 HES No. 3 Non-multiple extension Plan 4 (internal only) using Telephone No. 710
Q430 HES No. 3 Telephone Intercom No. 3/1 Locking Press-button
Q431 HES No. 3 Circuit Elements – Exchange line speech & ringing circuit. Installations with multiple stations only
Q432 HES No. 3 Circuit Elements - Exchange line engaged lamp and night service control
Q433 HES No. 3 Circuit Elements - Multiple intercom speech circuit
Q434 HES No. 3 Circuit Elements - Intercom signalling & station engaged circuit
Q435 HES No. 3 Circuit Elements - Power feeding circuit
Q441 HES No. 3 Provision of Relay Unit Q415 for terminating private and switchboard circuits on HES No. 3
Q442 HES No. 3 termination of private & interswitchboard circuits A/WE bothways
Q443 HES No. 3 Relay Unit Q415 Connected for G/AC in A/WE out
Q444 HES No. 3 termination of private & interswitchboard circuits Using Relay Unit Q415 signalling Loop in G/AC out or A/WE in G/AC out
Q445 HES No. 3 termination of private & interswitchboard circuits Using Relay Unit Q415 Signalling Group G/AC bothway
Q446 HES No. 3 termination of private & interswitchboard circuits Using Relay Unit Q415 signalling G/AC in Loop out
Q447 HES No. 3 termination of private & interswitchboard circuits Using Relay Unit Q415 signalling Balanced battery
Q500 HES No. 4 Numerical Index of Diagrams & EIs
Q501 HES No. 4 Alphabetical index of diagrams
Q502 HES No. 4 Layout of typical systems
Q503 HES No. 4 Cabling of typical systems (includes modification for loop ringing)
Q505 HES No. 4 Installations with a 2nd choice main station, block schematic & cabling
Q508 HES No. 4 Alternative system layout with spur multiple stations (typical)
Q509 HES No. 4 Provision of an eleventh station
Q510 HES No. 4 Box Connexion No. 6A, Connector No. 203
Q516 HES No. 4 Relay Unit Q516
Q519 HES No. 4 Relay Unit Q519 for terminating one non-multiple extension
Q524 HES No. 4 Relay Unit Q524 for terminating a private or switchboard circuit on HES No. 4
Q526 HES No. 4 Exchange service prohibited
Q527 HES No. 4 Exchange service restricted, relay units Q527 & Q528
Q529 HES No. 4 Regulator No. 4A
Q530 HES No. 4 Exchange line monitoring
Q531 HES No. 4 Buzzer No. 2B-3
Q535 HES No. 4 Control Unit Q535
Q537 HES No. 4 Control Unit Q537
Q540 HES No. 4 Telephone Intercom No. 4/1
Q545 HES No. 4 Extension bells and buzzers
Q546 HES No. 4 Alternative ringing arrangements
Q547 HES No. 4 Provision of Operator Recall
Q550 HES No. 4 Non-multiple extension using telephone No. 710
Q552 HES No. 4 Non-multiple extension Plan 1 (internal only) using Telephone No. 710
Q553 HES No. 4 Non-multiple extension Plan 1A (internal only) using Telephone No. 710
Q554 HES No. 4 Non-multiple extension Plan 4 (internal only) using telephone No. 710
Q561 HES No. 4 Provision of Relay Unit Q524 for terminating a private or switchboard circuit
Q562 HES No. 4 Termination of private and switchboard circuits using Relay Unit Q524 Signalling A/WE bothways
Q563 HES No. 4 Termination of private and switchboard circuits using Relay Unit Q524 Signalling G/AC in A/WE out
Q564 HES No. 4 Termination of private and switchboard circuits using Relay Unit Q524 Signalling G/AC in Loop out
Q565 HES No. 4 Termination of private and switchboard circuits using Relay Unit Q524 Signalling G/AC bothways
Q566 HES No. 4 Termination of private and switchboard circuits using Relay Unit Q524 Signalling A/WE in G/AC out
Q567 HES No. 4 Termination of private and switchboard circuits using Relay Unit Q524 Signalling Loop in G/AC out
Q568 HES No. 4 Termination of private and switchboard circuits using Relay Unit Q524 Signalling Auto Bal. Bat. Bothways
Q570 HES No. 3 and No. 4 Provision of hearing aid using Handset No. 4
Q580 HES No. 4 Circuit Elements Multiple stations exchange line speech ringing and signalling circuit
Q581 HES No. 4 Circuit Elements Multiple stations intercom speech and signalling circuits
Q582 HES No. 4 Circuit Elements Non-multiple stations intercom speech and signalling circuits
Q583 HES No. 4 Circuit Elements Non-multiple stations exchange line ringing speech & holding circuits & recall circuit

 

 

 
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Last revised: September 24, 2025

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